Tool Command Language (Tcl) is an interpreted language and very portable interpreter for that language. Tcl is embeddable and extensible, and has been widely used since its creation in 1988 by John Ousterhout.
Bug reports to http://core.tcl.tk/tcl/
Follow code development at http://core.tcl.tk/tcl/

After a program has been thrown into the world in binary form, it can boomerang back as source code. The Boomerang reverse engineering framework is the first general native executable decompiler available to the public.

X Certificate and Key management is an interface for managing asymetric keys like RSA or DSA. It is intended as a small CA for creation and signing certificates. It uses the OpenSSL library for the cryptographic operations.

MyGeneration is an extremely flexible template based code generator written in Microsoft.NET. MyGeneration is great at generating code for ORM architectures. The meta-data from your database is made available to the templates through the MyMeta API.

Barbecue is a Java library that enables the creation of barcodes in a variety of standard formats that can be displayed as Swing/AWT components, included in printed output, generated as EPS and SVG and displayed in a web application.

G3D is a commercial-grade C++ 3D engine. It is used in commercial games, research papers, military simulators, and university courses. G3D supports real-time rendering, off-line rendering like ray tracing, and general purpose computation on GPUs.

UPDATE: Chromium is no longer updated or maintained. The project is frozen.
Chromium is a flexible framework for scalable real-time rendering on clusters of workstations, derived from the Stanford WireGL project code base.

SpecTcl is a WYSIWYG GUI-Builder for Tcl/Tk, with sibblings for generating code in Perl, Java, Python & Ruby. It runs on all platforms where Tcl/Tk runs. It is simple and quick to use, yet still powerful when you know your Tcl/Tk.